In issuing an order and making a determination, the commission shall consider the facts and circumstances bearing on the reasonableness of emissions, including:
(1) the character and degree of injury to or interference with the public's health and physical property;
(2) the source's social and economic value;
(3) the question of priority of location in the area involved; and
(4) the technical practicability and economic reasonableness of reducing or eliminating the emissions resulting from the source.